Scientists led by NTU Singapore have developed and simulated a new energy-saving method that can produce highly focused and finely controlled X-rays that are a thousand times stronger than conventional methods.

This paves the way for ultra-high quality X-ray imaging that uses powerful X-rays to accurately detect defects in semiconductor chips. The new method could also use less energy and provide more focused X-ray imaging for health checks.

The new method, which is based on computer simulations, fires electrons at ultra-thin materials such as graphene that have a highly ordered structure. The basic mechanism is similar to the way a conventional X-ray tube produces X-rays. But there was a turning point: During the simulation, the wave-like motion patterns of the electrons were "shaped" in a very special way, so that the path of the particles matched and overlapped with the highly structured positions of the material's atoms.

The scientists used computers to simulate how electrons would pass through a special plate that also ran an electric current through it, creating a voltage. The scientists were able to show in simulations that the way electrons move after passing through this "phase plate" changes, an effect known as electron wave shaping.

Simulation results show that using the same current to emit electrons, the researchers' method produces X-rays a thousand times stronger than those produced by conventional methods using X-ray tube.